1. Field of the Invention
The present invention relates to a method of and apparatus for continuously discharging molten metal and slag from a furnace such as an electric induction furnace.
2. Description of the Related Art
Melting furnaces such as electric induction furnaces and arc furnaces have been used in which metals or metal compounds are molten and reduced by high thermal energy of electric heating. Discharge of molten metal and slag from such types of furnace is usually conducted by tilting the furnace or by breaking a bottom plug of the furnace, regardless of the capacity and yield.
The conventional discharging methods are quite dangerous and, hence, require experienced operators of a high level of skill. In addition, the operation of the whole furnace system has to be suspended during discharge.
The suspension of operation not only reduces the productivity but also requires a suitable counter-measure for preventing the temperature of the whole plant from dropping during the suspension.
In the conventional discharging method in which the melt is directly discharged from the furnace at high temperature, if the melt temperature is lowered in order to prevent generation of fumes which occurs when the discharge is conducted at high temperature, the fluidity of the slag is impaired to impede smooth discharge of the molten metal and the slag.